Women Who Drink Moderately Have Lower Stroke Risk

Good news for those of us who see a glass of wine at the end of the day as Mom's reward: Light to moderate drinking may reduce the risk of stroke in women.

Women who drink a glass of wine, beer or a mixed drink daily were less likely to have strokes compared to women who don't drink at all, according to a findings from an ongoing study that has followed the health of more than 80,000 women for 26 years.

The question of how alcohol affects the risk of stroke has been a question among scientists. Moderate drinking appears to lowers the risk of heart disease. It probably does that by boosting the production of HDL, the good cholesterol, and reducing the risk of blood clots.

Blood clots can cause the most common type of stroke, so fewer blood clots should mean fewer ischemic strokes. That's what this new study, which was published online today in the journal Stroke, found.

The researchers also found less risk of hemorrhagic stroke, which is caused by a burst blood vessel in the brain. Earlier studies have found more risk of hemorrhagic stroke, perhaps because a clot would be a good thing there.

"We didn't find much of a difference in the association with either type of stroke," Monik Jimenez, the epidemiologist at Brigham and Women's Hospital who led the study, tells Shots. "That's a bit different than what's been shown before."

The study looked at the health records of 83,578 women who participated in the Nurses' Health Study from 1980 to 2006. About 30 percent of the women didn't drink at all, and 35 percent reported very low alcohol intake – less than half a glass of wine a day. Just 4 percent said they drank 2 to 3 glasses of wine daily.

Because there were so few heavy drinkers, this study doesn't give a reliable picture of risk for women who drink heavily. But earlier studies have found that heavier drinking is linked to more strokes.

"At higher levels it can increase blood pressure," Jimenez says. Drinking a lot also can increase the risk of an irregular heartbeat called atrial fibrillation, which boosts the risk of stroke.

So this study isn't an invitation to booze it up. In fact, Jimenez says, women who don't drink can feel perfectly comfortable with that choice, because their risk of stroke is still relatively low. "We certainly don't want to advocate initiation of alcohol consumption for those who are non-drinkers."

The American Heart Association has a good overview on the relationship between alcohol and cardiovascular disease. They recommend no more than one to two drinks a day for men, and one a day for women.

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